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Re:I took down my Starlink dish (but haven't cancelled) by sidewndr46 on Thursday February 03, 2022 @10:18AM (#30193508)
I'm not an expert on the Starlink network, but their coverage isn't uniform. Even across the 48 states. The constellation provides more effective bandwidth in some areas than others.

SpaceX has a government subsidy to provide high speed internet right across the street from my parents house. But they have no satellite coverage in that area according to their own map. I don't really understand the business plan of SpaceX with respect to starlink.

Re:I took down my Starlink dish (but haven't cancelled) by gpm on Thursday February 03, 2022 @10:32AM (#30193679)
> But they have no satellite coverage in that area according to their own map.

There is nowhere in the lower 48 where starlink has no satellite coverage, I believe there are still areas where they have not built out ground stations though, and since most of the satellites don't have laser links to talk to other satellites (due to issues with their original lasers not fully burning up on re-entry - now fixed) they need to have a ground station under the same satellite as the customer.

They also have limited bandwidth to any one satellite, so they need to limit the density of their customers. Satellites move up and down lattitudes, but at any one time the density of satellites is higher at higher latitudes, so they should be able to serve more customers there.

Re:I took down my Starlink dish (but haven't cancelled) by sidewndr46 on Thursday February 03, 2022 @12:24PM (#30195424)
You're just arguing nuance & semantics.

For an ISP that uses satellites, ground stations are equivalent to satellite coverage. It doesn't matter how many satellites they have, if there isn't a ground station to connect to you don't have coverage.

Inter-satellite links also don't do anything useful if you don't have enough ground stations. Even if you had a ground station with infinite bandwidth there is no way a single satellite can have the entire network linked through it. It's a really neat thing to have a single voice channel connect through a constellation from somewhere like the southern Indian ocean, but you can't really run 100+ mbps pipes like that.

This is completely different than something like a military communications satellite where both ends of the connection are communicating through the same satellite. The 48 states could be totally in the dark (no power, no comms) and a military communications satellite still functions fine.

Re:I took down my Starlink dish (but haven't cancelled) by gpm on Thursday February 03, 2022 @01:01PM (#30196062)
I wasn't arguing, I was just adding nuance. Now I'm arguing though.

The nuance between ground station coverage and satellite coverage is extremely important for understanding spacex's business plan, which is relevant to your comment since you were saying "I don't really understand the business plan of SpaceX with respect tostarlink", with the implication that it doesn't make any sense. The difference between ground station coverage vs satellite coverage is the difference between "we're still building out the infrastructure, but we have the hard bits in place" and "this business model never scales because we need to launch way more satellites just to have basic coverage over the continent". It shouldn't be surprising that they're not done scaling the ground infrastructure, but that's not an impediment to their long term business model, because it's not the expensive bit.

> Even if you had a ground station with infinite bandwidth there is no way a single satellite can have the entire network linked through it.

This is a straw man, no one ever suggested that the entire network would be linked from a single satellite.

Rather the primary purpose of inter-satellite links is that you can expand coverage to areas away from ground stations. You route the traffic to a nearby groundstation (or better, a groundstation close to it's destination) with bandwidth available.

> but you can't really run 100+ mbps pipes like that.

Yes you can, I don't have numbers for starlink's inter-satellite links, but in general that technology is at the ~10gbps / laser link range, each satellite has 4. Light travels through space faster than in fiber, so if routed intelligently this actually lowers ping too.

> This is completely different than something like a military communications satellite where both ends of the connection are communicating through the same satellite.

Ironically, this actually describes how the current system works (as long as you treat the endpoint as a groundstation, and not an IP address somewhere on the internet).

The future system is more robust, even if there is no "other end" to talk to locally, spacex will (with inter-satellite links) be able to route you to an "other end" anywhere around the globe.

Re:I took down my Starlink dish (but haven't cancelled) by KennyBlanken on Thursday February 03, 2022 @01:41PM (#30196685)
> This is completely different than something like a military communications satellite where both ends of the connection are communicating through the same satellite.

Tell us you know nothing about military satcom without telling us you know nothing about military satcom.

Re:I took down my Starlink dish (but haven't cancelled) by sidewndr46 on Thursday February 03, 2022 @02:16PM (#30197289)
Well given that I worked on military comms for over a year I'd say I'm pretty knowlegeable.

Let's see, this system predates even my birth: https://en.wikipedia.org/wiki/Fleet_Satellite_Communications...

It's still in use as recently as 2009, by pirates however. Newer systems include some form of conditional access to prevent anyone with the gear from using them.

Re:I took down my Starlink dish (but haven't cancelled) by NovemberWhiskey on Thursday February 03, 2022 @05:00PM (#30199595)
I mean, OK, sure, but even Milstar Block I (mid-1990s tech) had a crosslink capability. And Milstar has already been folded into the the AEHF program, and the ESS program is already on track to replace AEHF.

It's a bit like saying "a bicycle is different from an automobile, because automobile frames are made from wood", and then pointing to a Morgan to prove the point.

Re:I took down my Starlink dish (but haven't cancelled) by colechristensen on Thursday February 03, 2022 @10:23AM (#30193560)
A lot of it has to do with satellite orbits, and basically the constellation is just far from complete.
Re:I took down my Starlink dish (but haven't cancelled) by HideousKojima on Thursday February 03, 2022 @10:51AM (#30193949)
Due to the orbits, the northern US has the highest concentration of sats. Specifically I think if you use the Washington-Oregon border and extend that line across the entire US that's roughly where the highest concentration is. That said, I think they already have full coverage in the entire lower 48.
Re:I took down my Starlink dish (but haven't cancelled) by JohnJamesRambo on Thursday February 03, 2022 @10:22AM (#30193548)
I don’t understand though. His cousin is 70 miles away, are the satellite coverages that small?
Re:I took down my Starlink dish (but haven't cancelled) by giantrobot on Thursday February 03, 2022 @11:29AM (#30194490)
The satellites just relay signals from a customer ground station to a Starlink-owned ground station. That ground station has a wired Internet connection.

So coverage at your house is dependent on you and a Starlink ground station being in the ground track of some Starlink satellites. Because of their low altitude it's entirely possible for your house being in the ground track of satellites but the nearest Starlink ground station being outside.

At some point in the future Starlink satellites will have laser communications between each other. Then only one in that group needs to be able to see a Starlink ground station and the others can route customer signals to it.

Re:I took down my Starlink dish (but haven't cancelled) by jagger27 on Thursday February 03, 2022 @10:36AM (#30193740)
It’s about the base station capacity, in theory. Though it seems super unlikely that an address that’s only 70 miles away would be on a different base station.

This will change dramatically once sat-to-sat laser comms are fully online as it will put more base stations “in range”.

Re:I took down my Starlink dish (but haven't cancelled) by jacquesm on Thursday February 03, 2022 @11:24AM (#30194407)
I'm not so sure about that. At 200 Km altitude that the footprint of the satellite wouldn't be all that large depending on the phase array arrangement. It might not be able to swing that far sideways and still get enough signal strength. These antennas don't move physically, the use phase based signal steering (black magic to me).
Re:I took down my Starlink dish (but haven't cancelled) by zyngaro on Thursday February 03, 2022 @06:34PM (#30200605)
Spacex business plan: Sucking tax payers money maybe ?